1. Field of the Invention
The present invention relates to a cable-type steering device, including a wire driving means connected to a steering wheel, and a wire follower means connected to a gear box for steering vehicle wheels, the wire driving means and the wire follower means being connected to each other by wires, so that a steering torque inputted to the steering wheel is transmitted to the gear box through the wires.
2. Description of the Related Art
In a conventional steering device for a vehicle, a steering shaft having a steering wheel at an upper end thereof is connected at its lower end to a gear box, so that a steering torque inputted to the steering wheel is transmitted through the steering shaft to a rack and pinion mechanism which is mounted within the gear box.
However, if the steering wheel and the gear box are connected to each other using the steering shaft, it is difficult to freely select the position of the steering wheel relative to the position of the gear box. For this reason, there is a problem in that the degree of design freedom is substantially limited. Also, the gear box cannot be commonly used in a right-hand steered vehicle and a left-hand steered vehicle. Moreover, another problem is that the vibration encountered by a tire from a road surface and the vibration of an engine are transferred to the steering wheel through the steering shaft and hence, the silence within a vehicle compartment and the riding comfort of the vehicle are impeded by such vibrations.
Therefore, there is a proposed cable-type steering device which employs a flexible transmitting means such as Bowden wire and the like, in place of the conventional steering shaft (see Japanese Patent Application Laid-open No. 7-117625).
If the construction of the proposed cable-type steering device is used, the position of the steering wheel relative to the position of the gear box can be freely selected and moreover, the vibration of the gear box is difficult to be transmitted to the steering wheel and hence, the above-described problems can be solved.
In a steering-wheel lock mechanism in the above conventional cable-type steering device, a locking pin appearing from and disappearing in a key cylinder engages a locking hole in a locking plate secured to an intermediate portion of an inner wire of the Bowden wire to inhibit rotation of the steering wheel.
In the above conventional steering device, however, it is required that the Bowden wires are disposed rectilinearly in a range in which a lock plate, as a rigid member, is moved. For this reason, a limitation to the handling of the Bowden wires is produced and hence, in some cases, it is difficult to mount the steering-wheel lock mechanism at a location near the steering wheel. In addition, the rotation of the steering wheel is inhibited by locking the Bowden wires and for this reason, in some cases, a load for rotating the steering wheel is applied directly to the Bowden wires to produce an elongation and a looseness of the Bowden wires.